Diehr P, Diehr G, Koepsell T, Wood R, Beach K, Wolcott B, Tompkins RK. Cluster analysis to determine headache types. J Chronic Dis. 1982;35(8):623-33.
Diehr P, Diehr G, Koepsell T, Wood R, Beach K, Wolcott B, Tompkins RK. Cluster analysis to determine headache types. J Chronic Dis. 1982;35(8):623-33.